Perforated tape



July 25, 1961 w. o. BRILLHART ET AL 2,993,812

PERFORATED TAPE Filed May 26, 1959 United States Patent 2,993,812 PERFORATED TAPE William 0. Brillhart, George W. Garner, and Robert W.

Park, Fredericksburg, Va., assignors to American Viscose Corporation, Philadelphia, Pa., a corporation of Delaware Filed May 26, 1959, Ser. No. 815,931 4 Claims. (01.117-157 This invention relates to perforated tape. More partioularly this invention relates to a fibrous reinforced durable flexible plastic perforated tape for actuating and controlling the operation of machinery.

'Many machines, such as calculating machines, automatic typewriters, machine tools and the like that perform a sequence of operations are actuated and controlled by means of a perforated tape. A mechanical means makes electrical contacts through the perforations or a jet of air or a beam of light passes through the perforations. For use on machines actuated by a beam of light, the tape must be opaque. Usually the tape for this purpose has an opaque layer of aluminum imbedded in or laminated to it. During use, the tape is flexed and is often folded together on itself for storage. Perforated tape of the prior art for this purpose is relatively expensive and has limited tear and crease or fold resistance.

This invention has for its principal object to provide a relatively inexpensive flexible perforated tape having improved durability, crease and fold resistance.

. A further object of the invention is to provide a relatively inexpensive dimensionally stable flexible durable perforated tape of cellulose plastic reinforced with fibrous material and having improved crease and fold resistance.

Other objects and advantages of the invention will be apparent from the following description and accompany ing drawings.

In the drawings:

FIGURE 1 is a diagrammatic view of a form of apparatus for impregnating and coating a fibrous web with cellulosic plastic to make the tape of this invention.

Y FIGURE 2 isa perspective veiw of a short length of perforated tape embodying the present invention.

FIGURE 3 is a sectional view greatly enlarged taken along line III, III of FIGURE 2.

In general, the perforated tape of the present invention comprises a light-weight, non-woven, porous fibrous web having high wet and dry strengths imbedded in or impregnated with a cellulosic plastic material that penetrates the pores or interstices of the web and surrounds or encloses the individual fibers of the web. The fibrous material extends throughout the area of the plastic sheet of this invention. For the fibrous web, there may be employed an open porous layer or layers of relatively long fibers which are formed into a sheet in which the fibers are in random distribution or arrangement as by blowing the fibers to form a web, by depositing the fibers from an aqueous dispersion, or by carding the fibers and cross lapping the carded webs. The fibers employed in the product are the longer vegetable fibers that are used in making high strength paper or other fibers that are longer than those normally employed in ordinary paper making and are disposed in the web in random arrangement. It is also characteristic of the fibrous web that it is relatively loose or highly porous and thin so that it can be readily penetrated and saturated with the film forming cellulosic materials. The fibers are preferably cellulosic such, for example, as rayon staple, hemp, jute, sisal, wood or other vegetable fibers at least some of which are longer than M inch. The cellulosic material is a cellulose ether having hydroxy units that serve to plasticize the plastic or a compatible mixture of regenerated cellulose and that cellulose ether. The plastic material may be formed from a compatible mixture of viscose and a cellulose ether, for example, alkali soluble water insoluble hydroxy ethyl cellulose. An alkaline solution of the cellulose ether or the cellulosic mixture is applied to one or both sides of the fibrous web which is then passed through pressure rolls to thoroughly impregnate the web and to imbed and coat the fibers with the plastic. The cellulose of the viscose is regenerated and the cellulose ether is precipitated in situ in and on the fibrous web by passing the coated web through an acid bath. If viscose is used in the coating, the coated web is then desulfun'zed, washed and dried. Additional plasticizing material such as glycerine or ethylene glycol or the like may be incorporated in the plastic sheet by adding this plasticizing material in the last liquid bath with which the sheet is treated before it is dried. Where the perforated tape is to be used on equipment that is actuated by a beam of light passing through the perforations in the tape, the tape may be made opaque by incorporating opaque materials such as carbon black, titanium dioxide, barium sulfate, and the like in the viscose and/or cellulose ether solution before it is applied to the fibrous web.

Referring to the drawing in which embodiments of the invention are illustrated, in FIGURE 1 reference character 2 indicates a web of fibrous sheet material such as high wet and dry strength tissue paper or woven or nonwoven textile fibrous material that is passed from a supply roll 3 to a coating device, generally indicated by reference character 4 by means of the guide roll 5. The coating device comprises a pair of pressure rollers 6 and 7 with end plates 8 to contain a well of liquid coating material supplied to the space between the upper portions of the rollers. The web is directed between the rollers through the liquid coating material. The rollers press the coating material into the web and thoroughly impregnate it. The

. amount of coating that is applied to the web is determined by the spacing between the rollers.

The coating liquid contains the viscose of such cellulose content and in such amounts and for the alkali soluble hydroxy ethyl cellulose in such amounts that the cellulosic plastic formed by this coating material comprises from 8 up to 100% cellulose ether and from 92 down to 0% regenerated cellulose. The cellulose ether has sufiicient hydroxy ethyl units to make the cellulose ether soluble in a dilute aqueous caustic solution. For most practical purposes, the hydroxy ethyl content may be from 5 to 10%. The viscose is the usual alkaline solution of cellulose xanthate. A suitable viscose for this invention contains a cellulose xanthate in an amount equivalent to 8.7% cellulose and 5.65% caustic soda by weight with the rest water. A suitable alkali soluble hydroxy ethyl cellulose solution in dilute caustic soda contains 7 /2% hydroxy ethyl cellulose and 7.5% sodium hydroxide by weight. The ethylene oxide equivalent of the hydroxy ethyl cellulose is 7.8% by weight.

After passing through the coating liquid and the pressing of the coating into the web, the coated and impregnated web is passed through the acid bath 10 where the cellulose of the viscose is regenerated and/or the cellulose ether is precipitated forming a compatible mixture of regenerated cellulose and hydroxy ethyl cellulose or the cellulose ether alone enclosing the individual fibers of the web and impregnating and filling the pores or interstices of the web.

In a preferred embodiment of the invention using these viscose and cellulose ether solutions, a suitable coating mixture may comprise 20% by weight of the cellulose ether solution and 80% by weight of the viscose. The amount of cellulosic plastic applied to the web may be varied. A suitable perforated tape may comprise by weight of the cellulosic plastic.

A suitable acid bath through which the coated web is passed may contain approximately 3.6% sulfuric acid, 12.5% sodium sulfate, and 23% ammonium sulfate. After passing through the acid bath the web is then passed through a desulfurizing liquid 11 and a plurality of washing baths such. as the bath 12. In the last Washing bath an additional plasticizer such as glycerine or ethylene glycol may be incorporated in the web. The web which is in the form of a plasticized cellulosic plastic reinforced with fibrous material imbedded therein is dried on the heated rollers 13 and collected on the take-up roller 14.

The reinforced plasticized plastic material is cut into relatively narrow strips 15 and is then perforated as at 16 in a predetermined pattern. as shown in FIGURE 2 to activate and control machinery in the desired manner. The perforations which are formed by .a. punching operation are shown as round but may have any other shape. The perforations have clear, sharp, tear-resistant edges and are entirely unobstructed by random fibers or frayed portions. When a tape isto be used over and over many times, the edge portions of the perforations may be further reinforced by treating with a dilute caustic soda solution in which the cellulose ether is soluble to enclose cut ends of the fibers in the cellulose ether. The individual fibers 17 as shown in the enlarged section in FIGURE 3 are entirely encased in the cellulosic plastic material. When both surfaces of the Web are subjected to the additional coating steps as shown in FIGURE 3, the surfaces 18 and 19 of the perforated tape are of cellulosic plastic material and are free of the fibrous material.

The perforated tape. of this invention is dimensionally stable during its ordinary and expected use and is durable and relatively inexpensive. The presence of the hydroxy ethyl groups of the cellulose ether as well as the added plasticizer serve to lubricate the punch and facilitate the punching operation.

In many instances the perforated tape is used over and over again and is folded and stored between times of use. The hydroxy ethyl units which are not fugitive but remain in the plastic throughout the life of the perforated tape serve as an internal plasticizer and increase the flex life as well as the fold and crease resistance of the tape.

While preferred embodiments of the invention have been shown and described, it is to be understood that changes and variations may be made without departing from the spirit and scope of the invention as defined in the, appended claims.

We claim:

1. A perforated flexible tape for machines actuated and controlled by the perforations therein, that is a strip of cellulosic plastic material comprising a compatible mixture of regenerated cellulose and alkali soluble hydroxy ethyl cellulose having a reinforcing layer of fibrous material of substantially the same area as the strip imbedded 4 therein with the cellulosic plastic material extending through the fibrous layer and surrounding and enclosing individual fibers thereof, at least some of the fibers being more than 3 in length, the tape having perforations formed therein in a predetermined pattern and having sharp tear-resistant surrounding portions and being free of projecting fibers.

2. A perforated flexible tape for machines actuated and controlled by the perforations therein, that is a strip of cellulosic plastic material comprising a mixture of regenerated cellulose and alkali soluble hydroxy ethyl cellulose having a reinforcing layer of fibrous material of substantially the same area as the strip imbedded therein with the cellulosic plastic material extending through the fibrous layer and surrounding and enclosing individual fibers thereof, the hydroxyethyl cellulose accounting for at least 8% of the cellulosic plastic material, the tape having perforations formed therein in a predetermined pattern and having sharp tear-resistant surrounding portions and being free of projecting fibers.

3. A perforated flexible tape for machines actuated and controlled by the perforations therein, that is a strip of cellulosic plastic material comprising a compatible mixture of approximately regenerated cellulose and approximately 20% alkali soluble hydroxy ethyl cellulose having a reinforcing layer of fibrous material of substantially the same area as the strip imbedded therein with the cellulosic plastic material extending through the fibrous layer and surrounding and enclosing individual fibers thereof, the tape having perforations formed therein in a predetermined pattern and having sharp tear-resistant surrounding portions and being free of projecting fibers.

4. A perforated flexible tape for machines actuated and controlled by the perforations therein, that is a strip of cellulosic plastic material comprising a compatible mixture of about 80% regenerated cellulose and about 20% alkali soluble hydroxyethyl cellulose, said hydroxyethyl cellulose having a hydroxyethyl content of between about 5% and about 10%, a reinforcing layer of fibrous material of substantially the same area as the strip imbedded therein with the cellulosic plastic material extending through the fibrous layer and surrounding and enclosing individual fibers thereof, the tape having perforations formed therein in a predetermined pattern and having sharp tearresistant surrounding portions and being free of projecting fibers.

References Cited in the file of this patent UNITED STATES PATENTS 158,442 Sawyer Jan. 5, 1875 2,031,854 Richter Feb. 25, 1936 2,124,330 Pascoe et a1 July 19, 1938 2,502,782 Erickson Apr. 4, 1950 

1. A PERFORATED FLEXIBLE TAPE FOR MACHINES ACTUATED AND CONTROLLED BY THE PERFORATIONS THEREIN, THAT IS A STRIP OF CELLULOSIC PLASTIC MATERIAL COMPRISING A COMPATIBLE MIXTURE OF REGENERATED CELLULOSE AND ALKALI SOLUBLE HYDROXY ETHYL CELLULOSE HAVING A REINFORCING LAYER OF FIBROUS MATERIAL OF SUBSTANTIALLY THE SAME AREA AS THE STRIP IMBEDDED THEREIN WITH THE CELLULOSIC PLASTIC MATERIAL EXTENDING THROUGH THE FIBROUS LAYER AND SURROUNDING AND ENCLOSING INDIVIDUAL FIBERS THEREOF, AT LEAST SOME OF THE FIBERS BEING MORE THAN 1/16" IN LENGTH, THE TAPE HAVING PERFORATIONS FORMED THEREIN IN A PREDETERMINED PATTERN AND HAVING SHARP TEAR-RESISTANT SURROUNDING PORTIONS AND BEING FREE OF PROJECTING FIBERS. 